Diethylaminoethylated cellulose-acid anhydride reaction products

ABSTRACT

THE TERTIARY AMINE GROUPS OF DIETHYLAMINOETHYL COTTON ACT AS AN INTERNAL CATALYST FOR THE REACTION OF CELLULOSE HYDROXYLS WITH ANHYDRIDES TO FORM ESTERS. THE CELLULOSE ESTERS ARE STABLE TO MILD ACID STEEPING AND UNSTABLE UNDER MILD BASIC CONDITIONS. ANHYDRIDES CONTAINING HALOGEN ATOMS YIELD PRODUCTS WITH INCREASED RESISTANCE TO ROT.

United States Patent Office US. Cl. 260-226 3 Claims ABSTRACT OF THE DISCLOSURE The tertiary amine groups of diethylaminoethyl cotton act as an internal catalyst for the reaction of cellulose hydroxyls with anhydrides to form esters. The cellulose esters are stable to mild acid steeping and unstable under mild basic conditions. Anhydrides containing halogen atoms yield products with increased resistance to rot.

A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to the modification of diethylaminoethyl cotton cellulose by acid anhydrides. The builtin amine groups of diethylaminoethylated cotton function as catalyst for the reaction. Specifically, this invention relates to the formation of cellulose esters of diethylaminoethyl, which esters possesses rot resistant properties, by a process of reacting the cellulose hydroxyls, under the specific catalytic effect of the tertiary amine groups of the diethylaminoethylated cotton with the organic acid anhydride, 1,4,5,6,7,7 hexachlorobicyclo- [2.2.1]-5-heptene-2,3-dicarboxylic acid anhydride and tetrabromophthalic anhydride.

The main object of this invention is to provide a process for esterifying diethylaminoethyl cellulosic materials. A further object is to utilize the built-in amine groups of diethylaminoethylated cottons as the catalyst for the esterifying process. Another object is to impart rot resistance to diethylaminoethyl cellulose materials by forming the cellulose esters thereof with halogenated acid anhydrides.

The esters of this invention are stable to acid and neutral hydrolysis but are susceptible to basic hydrolysis. Anhydrides containing a variety of groups or atoms other than halogen atoms can be introduced into aminized cellulose by this method. Extreme reaction conditions characteristic of conventional esterifications are not necessary to produce esters by the process of this invention. Crosslinking of the cellulose can be achieved by employing active dibasic acid anhydrides.

The various anhydrides investigated were hexanoic, glutaric, maleic, pyrotartaric, citraconic, tetraiodophthalic, 7- oxabicyclo [2.2.1]hept 5 ene 2,3-dicarboxylic, 4- methyl 4 cyclohexene-1,2-dicarboxylic, maleo-pimaric acid, S-norbornene-Z,3-dicarboxylic acid, tetrabromo 3,585,190 Patented June 15, 1971 phthalic, 1,4,5 ,6,7,7-hexachlorobicyclo- [2.2. 1 -5-heptene- 2,3 dicarboxylic, and [2.2.1]-5-heptene-2,3-dicarboxylic acid anhydride.

EXAMPLE 1 Diethylaminoethylated cotton of 1.00% nitrogen and untreated cotton were placed in a 20% by weight solution of l,4,5,6,,7,7 hexachlorobicyclo [2.2.l]-5-heptene-2,3- dicarboxylic (chlorendic) anhydride in acetone for 24 hours at room temperature. After washing in acetone, then methanol and finally water, the esterified diethylaminoethylated cotton contained 3.30% chlorine and the esterified control cotton 0.34% chlorine. Rot resistance of the two is set forth in the table below. The esterified diethylaminoethylated cotton retained of its breaking strength after soil burial for 33 days in an activated bed whereas the esterified control cotton was destroyed completely after only 13 days.

TABLE I Breaking strength (1b.) -Bt1rial for- 0 days 13 days 35 days 94 days Treated sample Diethylamincethyl. Untreated percent EXAMPLE 2 TABLE II Breaking strength (lb.)Burial for- 13 days 35 days 94 days percent Treated sample Diethylamino ethyl- Untreated 0 days EXAMPLE 3 Diethylaminoethylated cotton of 0.80% nitrogen was treated at room temperature in a 20% solution of the following anhydrides in acetone for 24 hours.

TABLE III Wrinkle recover IR absor t'o l Anhydrides Add-on, (W-FF)" (micror l s) n wt., Name Formula percent Wet 00nd. Ester COO- Hexanoie [(CH ((3H2)4]2A 2.0 187 198 5.75(M) 6.35(M) Glutarie CH1 12.8 243 146 Malclc CH\ 8.4 233 16'.) 5.80(M) 6.150(8) H A ClI lyrotartarie CII3CII\ 5.3 186 202 5.113(8) 6.152(8) A CH2 Gitrueonic CH-C 4.0 147 230 5.76(Sh) 6.50(S) /A CH Tctraiodophthalic 3 II 3. 5 205 197 5.77(S) 627(5) 7-oxabicyclo[2.2.llhept-S-ene-Z,3- 3.8 166 209 5.77 S 6.27 S

dicarboxylie.

I} 0 DA \l/ 4-methyl-4-cyclol1cxeuc-1,2- 5.3 182 233 5.77(M) 6.33(M) dicarboxylic.

1\Ialcopimaric acid. 1.6 182 228 5.76(S h) 6.3303) H0 0 0 CH3 5-norborncnc-2, Z-dicarb 0x ylie DEAE control l (S) strong; (M) medium; (B) broad; (Sh) shoulder. 2 A represents an anhydride group.

3 Reacted at room temperature in a 20% solution of the anhydride in dimethylformamide.

We claim: 1. A process for esterifying fibrous diethylaminoethyl cotton cellulose with an organic acid anhydride which process consists in its entirety of reacting fibrous diethylaminoethyl cotton cellulose, at room temperature and for a time interval of at least 24 hours, with an excess of the organic acid anhydride to produce the fibrous ester.

2. The process for esterifying fibrous diethylaminoethyl cotton cellulose with 1,4,5,6,7,7 hexachlorobicyclo- [2.2.1]-5-heptene-2,3-dicarboxylic anhydride, which process comprises reacting, at room temperature and for a time 75 6 brous diethylaminoethyl cotton cellulose with a solution 2,856,399 10/1958 Mench et a1. 260224 of dimethylformamide containing an excess of 3,4,5,6 3,051,698 8/1962 Elizer et a1. 260224 tetrabromo-1,2-phthalio anhydride and freeing the result- 3,359,258 12/1967 Toms 2 60-232 ing fi brous cellulosic reaction product from unreacted anhyd nde reagent by washing serially with dimethylform- 5 DONALD E. CZAJA, Primary Examiner am1de, methanol, and water.

R. W. GRIFFIN, Assistant Examiner References Cited UNITED STATES PATENTS 8-129; 260-232 2,825,623 3/1958 Stephens et a1 260-232 10 2,852,508 9/1958 Hiatt et a1 260-226 

